Components that lie on a circuit board typically have leads or tails that must be soldered to traces on the circuit board. One technique for mounting the tails includes drilling holes through the circuit board, plating the holes and then fixing the tails in the holes. The tail can be a compliant pin which is forced into the hole in an interference fit, or can be soldered in place with the solder joined to tail portions that project from opposite ends of the hole. When a multi-layer circuit board assembly is used, the through holes extending the board assembly are long and tails to be soldered in the holes must be long. This results in considerable capacitance between the plated walls of the hole and close traces on the laminates, or layers of the assembly, and results in increased crosstalk and decreased signal strength.
Another technique for soldering component tails to traces on a circuit board, is the SMT (surface mount technique) method, wherein the tails touch circuit board traces that form solder pads, and are soldered thereto. In order to achieve reliable solder joints, the tails should each touch the corresponding solder pad. This requires close tolerances and/or resilient tails. The SMT technique results in solder joints that are mechanically weak, against shear forces that tend to move the tails parallel to the plane of the board upper face and against pull up forces.
A technique for soldering component tails to platings or other traces on a multilayer circuit board, which avoided the disadvantages of high capacitive load for through-hole soldering, and which avoided the disadvantages of weakness and close tolerances or resilient tails for SMT, would be of value.